Invention relates to electronic networks, particularly network protocol for frame relay fragmentation for supporting real-time digital voice traffic.
Various networking equipment and interfaces, such as frame relay-based access devices and switches, increasingly are used for communicating digital voice messages, as well as conventional data. Typically, fragmentation of communicated messages for network transmission is supported for many data applications.
However, without a suitable control protocol, the fragmentation operation may encounter certain problems. For example, fragmentation must be configured statistically for all virtual circuits (VCs) to all destinations, and all fragmentation must be activated at all times. This would be an inefficient use of system resources and wide-area network (WAN) access bandwidth, particularly when there is no voice call.
Additionally, another problem may arise when both peers of the virtual circuit must configure correctly the fragment packet size to reflect the speeds of the physical interface and requirement for voice coder/decoder (codec), but there is no safeguard necessarily when the fragment packet size configured is acceptable for operation. Hence, when the fragment packet size is incorrect, then undesirable latency may result.
Furthermore, another problem may arise due to the nature of the fragmentation being all VCs that share the same interface perform fragmentation concurrently, such that many (e.g., tens or hundreds) of VCs demand fragmentation with all their peers across the network. Thus, without a control protocol, it is difficult to determine fragmentation capability at the remote end. If one side of the virtual circuit is configured for fragmentation, and the other end is not, then the whole virtual circuit may fail.
Moreover, generally, as higher-speed or real-time traffic, particularly voice or video based information, is transmitted over the network, there is a need for improved protocol for supporting such real-time applications, particularly for controlling frame-relay fragmentation.
Invention resides in a Frame Relay (FR) fragmentation control protocol (FCP) and/or system for enabling FR access device and switches to support real-time traffic, such as Voice over Internet Protocol (VOIP) and Voice over Frame Relay (VOFR). Preferred FR control protocol enables communicating peers to negotiate dynamically for fragmentation operation and configuration parameters, as well as operation termination. Such protocol applies to FR User to Network Interface (UNI) fragmentation and end-to-end fragmentation.
Generally, in a digital network including various routers coupled for frame relay networking, a novel fragmentation control protocol is implemented such that initially multiple peer units are determined in at least one virtual circuit for frame relay-based signaling through one or more interfaces, then fragmentation is selectively provided to the virtual circuit(s).
Fragmentation is deployable on demand, and configuration negotiation is supportable across the network. Preferably, such control protocol allows systems with fragmentation to interoperate with older systems that do not support fragmentation.